Field of the Invention
The invention relates to an integrated circuit and a method of fabricating the same; more particularly, the invention relates to a semiconductor and a method of fabricating the same.
Description of Related Art
Magnetic random access memory (MRAM) has advantages of fast speed, low power consumption, high density, non-volatile, and has almost unlimited read and write times, and is predicted as a mainstream of memories coming in the next generation. A basic structure of MRAM is formed by a pinned layer, a barrier layer and a free layer. By changing a magnetization direction of the free layer to be parallel or antiparallel to a magnetization direction of the pinned layer, a magnetoresistance thereof respectively has a low resistance state and a high resistance state for storing information.
A spin transfer torque (STT) MRAM is regarded as a memory of the new generation, which records digital information of 0 and 1 through spin transfer switching. Specifically, the STT mechanism, by which an angular momentum conservation mechanism of spin-polarized electrons and a local magnetic moment is used to switch the magnetization direction of the free layer of the device, so as to implement the write operation. A STT write current is proportional to a device size, which avails miniaturization. Takes the STT-MRAM as a main magnetic memory cell structure, which has better endurance, reliability, and an operating current thereof is smaller compared with that of the other type of the memory, such as SRAM, DRAM, or RRAM. Therefore, STT-MRAM is better suited for embedded working memory.